Lab

Lactose Breath Hydrogen Test

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Lactose Breath Hydrogen Test

  • Indications
  • Efficacy
  • Technique
  1. Measure baseline breath hydrogen concentration
  2. Patient ingests lactose
    1. Classic: 25 to 50 grams lactose
    2. Physiologic: 12 grams lactose (same as in 8 oz milk)
  3. Measure breath hydrogen concentration in 3 to 8 hours
    1. Increase >20 ppm suggests Lactose Intolerance
  • False Negative causes
  1. Gastrointestinal flora absent (e.g. recent antibiotics)
  • False Positive causes
  • References
  1. Powell in Goldman (2000) Cecil Medicine, p. 711